Description of Plan - Addition Information (Detail) - EBP 002 [Member] - USD ($)	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024
EBP, Description of Plan [Line Items]
Ebp, employer contribution, matching percentage	100.00%
Ebp, employer contribution, participant compensation matched, percentage	6.00%
Employee benefit plan deferral eligible compensation percentage	6.00%
Employee benefit plan increases of deferral eligible compensation percentage	1.00%
Employee benefit plan increases of maximum deferral eligible compensation percentage	10.00%
Employee benefit plan investment in specified fund percentage	1.00%
Employee benefit plan participants are fully vested in their contributions percentage	25.00%
Ebp, forfeited nonvested account	$ 238,011	$ 140,855
Ebp, forfeited nonvested account, decrease from administrative expense	185,016
Ebp, forfeited nonvested account, decrease from employer contribution	12,237
Other income – revenue sharing	145,500
Employee benefit plan allocated to eligible plan participants	121,600
Employee benefit plan allocated to plan expenses	15,400
Employee benefit plan revenue credit account remain balance	$ 70,900	$ 60,000
Employee benefit plan penalty and applicable income tax	10.00%
Employee benefit plan participant with vested balance	$ 7,000
Employee benefit plan participant with distribution	$ 1,000
Ebp, note receivable from participant, account, maximum borrowing, to total account, percentage	50.00%
Ebp, note receivable from participant, account, maximum borrowing, amount	$ 50,000
Ebp, note receivable from participant, account, minimum borrowing, amount	$ 1,000
Note Receivable From Participant [Member]
EBP, Description of Plan [Line Items]
Employee Benefit Plan Employer Participant Loan Interest Percentage Description	prime rate plus 2%
Maximum [Member]
EBP, Description of Plan [Line Items]
Ebp, participant contribution, pretax, maximum annual compensation to total compensation, percentage	100.00%
Employee benefit plan interest loan outstanding percentage	10.50%
Minimum [Member]
EBP, Description of Plan [Line Items]
Ebp, participant contribution, pretax, maximum annual compensation to total compensation, percentage	1.00%
Employee benefit plan interest loan outstanding percentage	5.25%

Employee benefit plan allocated to eligible plan participants.

No definition available.

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Namespace Prefix:	ing_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Employee benefit plan allocated to plan expenses.

+ References

No definition available.

+ Details

Name:	ing_EmployeeBenefitPlanAllocatedToPlanExpenses
Namespace Prefix:	ing_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Employee benefit plan deferral eligible compensation percentage.

+ References

No definition available.

+ Details

Name:	ing_EmployeeBenefitPlanDeferralEligibleCompensationPercentage
Namespace Prefix:	ing_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Employee benefit plan employer participant loan interest percentage description.

+ References

No definition available.

+ Details

Name:	ing_EmployeeBenefitPlanEmployerParticipantLoanInterestPercentageDescription
Namespace Prefix:	ing_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Employee benefit plan increases of deferral eligible compensation percentage.

+ References

No definition available.

+ Details

Name:	ing_EmployeeBenefitPlanIncreasesOfDeferralEligibleCompensationPercentage
Namespace Prefix:	ing_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Employee benefit plan increases of maximum deferral eligible compensation percentage.

+ References

No definition available.

+ Details

Name:	ing_EmployeeBenefitPlanIncreasesOfMaximumDeferralEligibleCompensationPercentage
Namespace Prefix:	ing_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Employee benefit plan interest loan outstanding percentage

+ References

No definition available.

+ Details

Name:	ing_EmployeeBenefitPlanInterestLoanOutstandingPercentage
Namespace Prefix:	ing_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Employee benefit plan investment in specified fund percentage.

+ References

No definition available.

+ Details

Name:	ing_EmployeeBenefitPlanInvestmentInSpecifiedFundPercentage
Namespace Prefix:	ing_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Employee benefit plan other income revenue sharing.

+ References

No definition available.

+ Details

Name:	ing_EmployeeBenefitPlanOtherIncomeRevenueSharing
Namespace Prefix:	ing_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Employee benefit plan participant with distribution.

+ References

No definition available.

+ Details

Name:	ing_EmployeeBenefitPlanParticipantWithDistribution
Namespace Prefix:	ing_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Employee benefit plan participant with vested balance.

+ References

No definition available.

+ Details

Name:	ing_EmployeeBenefitPlanParticipantWithVestedBalance
Namespace Prefix:	ing_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Employee benefit plan participants are fully vested in their contributions percentage.

+ References

No definition available.

+ Details

Name:	ing_EmployeeBenefitPlanParticipantsAreFullyVestedInTheirContributionsPercentage
Namespace Prefix:	ing_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Employee benefit plan penalty and applicable income tax.

+ References

No definition available.

+ Details

Name:	ing_EmployeeBenefitPlanPenaltyAndApplicableIncomeTax
Namespace Prefix:	ing_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Employee benefit plan revenue credit account remain balance.

+ References

No definition available.

+ Details

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Namespace Prefix:	ing_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)
-SubTopic 205
-Topic 962
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478416/962-205-50-1

+ Details

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Namespace Prefix:	us-gaap-ebp_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage of employer matching contribution on eligible participant contribution to employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

+ References

+ Details

Name:	us-gaap-ebp_EmployeeBenefitPlanEmployerContributionMatchingPercentage
Namespace Prefix:	us-gaap-ebp_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage of participant compensation eligible for employer matching contribution for participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

+ References

+ Details

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Namespace Prefix:	us-gaap-ebp_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of plan asset, in forfeited nonvested account, no longer allocated to participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

+ References

+ Details

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Namespace Prefix:	us-gaap-ebp_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of decrease in forfeited nonvested account of employee stock purchase, saving, or similar plan (employee benefit plan (EBP)) from administrative expense.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 962
-SubTopic 205
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (j)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478416/962-205-50-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 962
-SubTopic 205
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6A-04(5)(c))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477804/962-205-S99-1

+ Details

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Namespace Prefix:	us-gaap-ebp_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of decrease in forfeited nonvested account of employee stock purchase, saving, or similar plan (employee benefit plan (EBP)) from employer contribution.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 962
-SubTopic 325
-Name Accounting Standards Codification
-Section 55
-Paragraph 17
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478873/962-325-55-17

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 962
-SubTopic 205
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (j)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478416/962-205-50-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 962
-SubTopic 205
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6A-04(5)(c))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477804/962-205-S99-1

+ Details

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Namespace Prefix:	us-gaap-ebp_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of maximum account balance that participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)) can borrow.

+ References

+ Details

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Namespace Prefix:	us-gaap-ebp_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Percentage of maximum account balance that participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)) can borrow to total participant account balance.

+ References

+ Details

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Namespace Prefix:	us-gaap-ebp_
Data Type:	dtr-types:percentItemType
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Period Type:	instant

- Definition

Amount of minimum account balance that participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)) can borrow.

+ References

+ Details

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Namespace Prefix:	us-gaap-ebp_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Percentage of maximum pretax annual compensation that participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)), is permitted to contribute to total pretax annual compensation.

+ References

+ Details

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Namespace Prefix:	us-gaap-ebp_
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- Details

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- Details

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- Details

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